From 9315e2f08ea20d021bf7a34c1aa9453499d063f7 Mon Sep 17 00:00:00 2001
From: Laurenz <laurmaedje@gmail.com>
Date: Fri, 17 Mar 2023 18:51:42 +0100
Subject: [PATCH] Make parameters traceable

---
 src/eval/func.rs | 29 ++++++++++++++---------------
 src/eval/mod.rs  |  8 ++++----
 2 files changed, 18 insertions(+), 19 deletions(-)

diff --git a/src/eval/func.rs b/src/eval/func.rs
index af80ac92c..14da5ff08 100644
--- a/src/eval/func.rs
+++ b/src/eval/func.rs
@@ -5,7 +5,6 @@ use std::hash::{Hash, Hasher};
 use std::sync::Arc;
 
 use comemo::{Prehashed, Track, Tracked, TrackedMut};
-use ecow::EcoString;
 use once_cell::sync::Lazy;
 
 use super::{
@@ -14,7 +13,7 @@ use super::{
 };
 use crate::diag::{bail, SourceResult, StrResult};
 use crate::model::{Introspector, NodeId, Selector, StabilityProvider, StyleMap, Vt};
-use crate::syntax::ast::{self, AstNode, Expr};
+use crate::syntax::ast::{self, AstNode, Expr, Ident};
 use crate::syntax::{SourceId, Span, SyntaxNode};
 use crate::util::hash128;
 use crate::World;
@@ -294,14 +293,14 @@ pub(super) struct Closure {
     /// The source file where the closure was defined.
     pub location: SourceId,
     /// The name of the closure.
-    pub name: Option<EcoString>,
+    pub name: Option<Ident>,
     /// Captured values from outer scopes.
     pub captured: Scope,
     /// The parameter names and default values. Parameters with default value
     /// are named parameters.
-    pub params: Vec<(EcoString, Option<Value>)>,
+    pub params: Vec<(Ident, Option<Value>)>,
     /// The name of an argument sink where remaining arguments are placed.
-    pub sink: Option<EcoString>,
+    pub sink: Option<Ident>,
     /// The expression the closure should evaluate to.
     pub body: Expr,
 }
@@ -329,14 +328,19 @@ impl Closure {
         let mut scopes = Scopes::new(None);
         scopes.top = closure.captured.clone();
 
+        // Evaluate the body.
+        let vt = Vt { world, tracer, provider, introspector };
+        let mut vm = Vm::new(vt, route, closure.location, scopes);
+        vm.depth = depth;
+
         // Provide the closure itself for recursive calls.
         if let Some(name) = &closure.name {
-            scopes.top.define(name.clone(), Value::Func(this.clone()));
+            vm.define(name.clone(), Value::Func(this.clone()));
         }
 
         // Parse the arguments according to the parameter list.
         for (param, default) in &closure.params {
-            scopes.top.define(
+            vm.define(
                 param.clone(),
                 match default {
                     Some(default) => {
@@ -349,20 +353,15 @@ impl Closure {
 
         // Put the remaining arguments into the sink.
         if let Some(sink) = &closure.sink {
-            scopes.top.define(sink.clone(), args.take());
+            vm.define(sink.clone(), args.take());
         }
 
         // Ensure all arguments have been used.
         args.finish()?;
 
-        // Evaluate the body.
-        let vt = Vt { world, tracer, provider, introspector };
-        let mut sub = Vm::new(vt, route, closure.location, scopes);
-        sub.depth = depth;
-
         // Handle control flow.
-        let result = closure.body.eval(&mut sub);
-        match sub.flow {
+        let result = closure.body.eval(&mut vm);
+        match vm.flow {
             Some(Flow::Return(_, Some(explicit))) => return Ok(explicit),
             Some(Flow::Return(_, None)) => {}
             Some(flow) => bail!(flow.forbidden()),
diff --git a/src/eval/mod.rs b/src/eval/mod.rs
index a7f4b8256..e6da6cba5 100644
--- a/src/eval/mod.rs
+++ b/src/eval/mod.rs
@@ -1140,7 +1140,7 @@ impl Eval for ast::Closure {
 
     fn eval(&self, vm: &mut Vm) -> SourceResult<Self::Output> {
         // The closure's name is defined by its let binding if there's one.
-        let name = self.name().map(ast::Ident::take);
+        let name = self.name();
 
         // Collect captured variables.
         let captured = {
@@ -1156,16 +1156,16 @@ impl Eval for ast::Closure {
         for param in self.params() {
             match param {
                 ast::Param::Pos(name) => {
-                    params.push((name.take(), None));
+                    params.push((name, None));
                 }
                 ast::Param::Named(named) => {
-                    params.push((named.name().take(), Some(named.expr().eval(vm)?)));
+                    params.push((named.name(), Some(named.expr().eval(vm)?)));
                 }
                 ast::Param::Sink(name) => {
                     if sink.is_some() {
                         bail!(name.span(), "only one argument sink is allowed");
                     }
-                    sink = Some(name.take());
+                    sink = Some(name);
                 }
             }
         }